1. Field of the Invention
This application relates to manufacturing products and components from polymer materials. More specifically, this application provides a method and apparatus for joining polymers. More particularly, this application relates to fabricating a processing chamber for use in semiconductor fabrication.
2. Description of the Related Art
Many devices and products are manufactured from polymers. In the manufacture of a polymer product, the product, or a component of the product, is typically formed by molding, extrusion, machining, or other forming process. Generally, the material used is a solid at a predetermined temperature, which may be at or near room temperature, but is capable of transition to an interphase state between a liquid and a solid when heated. The material may be capable of being heated to a viscous or semi-viscous state and returning to a non-viscous state without significant degradation. Thus, the material may be capable of processing by heat application to at least a portion of the material and, after cooling, the material returns to a more solidified state.
Polymer components may be joined together to make the product or subassembly. Conventional joining includes solvent bonding, adhesive bonding, fastening, and various techniques generally referred to as plastic welding. Plastic welding typically includes applying heat, and in some applications, pressure, to at least a portion of the interface of two or more polymer components. The heat may be produced by heated fluids applied to the interface, friction, high-frequency electromagnetic waves, high-frequency sound waves, laser, convection, or other suitable application. In some of these processes, a filler material may be added during the heat application to fill gaps or form a weld bead.
Although there are numerous joining methods available, some product applications may not be capable of joining by conventional methods. For instance, some materials may be resistant to adhesives and solvents, and some of the conventional methods may also promote oxidation and/or particle generation, which may be detrimental in product applications where purity of the material must be maintained. The conventional methods may also distort the product due to uneven or excessive heat application. Further, some of the conventional methods require line of sight application and/or are difficult to use with interfaces having small dimensions, which may require the manufacturer to alter the product in order to join its components. Also, it may be desirable to join the components where a weld or joint is internal to the finished product, which may be difficult or impossible to accomplish with the conventional methods.
Another joining method has been developed and uses electrical resistance, sometimes known as resistive implant welding, electrical-resistance fusion, or electro-fusion. A conductive insert, such as a wire or metal mesh, is positioned at the interface of the components to be joined. The insert and subsequently the surrounding material are heated up by the resistive effect of electric current applied to the insert. Upon reaching a viscid or semi-viscid state, the two surfaces are joined and the insert remains in place with no further use. However, there are product applications where the remaining insert may be problematic. For instance, the insert may react magnetically and/or electrically when the product is in operation, which may be detrimental to the product and/or the process performed within the product.
The present application minimizes or solves the problems mentioned above by providing a method and apparatus to join two or more polymer components together. The method is useful, for example, for forming a chamber for use in processing a semiconductor substrate.